The "solvatochromic parameter" data base will be expanded and solubility, distribution, and toxicology properties (XYZ) of organic nonelectrolytes will be correlated, rationalized, and predicted through linear solvation energy relationships of the form: XYZ = XYZo + mV/100 + sPI* + a alpha + b beta V is a measure of solute (toxicant) molar volume, and pi*, alpha, and beta are the solvatochromic parameters that measure solute dipolarity/polarizability, hydrogen bond donor acidity, and hydrogen bond acceptor basicity. Properties to be correlated and predicted include aqueous solubilities and toxicities of liquid and solid solutes, solubilities of liquid solutes in human body tissues and fluids, and equilibrium distributions of liquid and solid solutes (including candidate pharmaceuticals and carcinogens) among these tissues. The correlation equations will provide synthesis guidelines for "targeting" of candidate pharmaceuticals toward or away from specific body organs.